A 72-year-old woman with multiple comorbidities was diagnosed with severe aortic stenosis (AS) and mitral stenosis (MS). Contrast-enhanced computed tomography revealed remarkable calcification of the annulus from the posterior leaflet to the posterior commissure. Considering the potentially fatal complications associated with excising the calcification, chimney mitral valve replacement (MVR) was performed. Furthermore, aortic valve replacement was performed for severe AS. Transthoracic echocardiography 14 months after surgery revealed normal valve motion and no perivalvular regurgitation. Thus, chimney MVR was deemed useful for MS with severe mitral annular calcification, as in this case.